Zoology and wildlife conservation

What killed the monk seals?

Article Abstract:

It is possible that the more than 100 Mediterranean monk seals found dead in May and Jun 1997 along the Cap Blanc peninsula, situated on the border between Mauritania and the former Western Sahara, were killed by eating fish contaminated with phycotoxins. Researchers from the University of Barcelona, Spain, found several phycotoxins in the dead seals, along with high concentrations of the dinoflagellate Alexandrium minutum in the coastal waters. It is not possible to state with certainty that the toxins killed the seals, as there is no information about lethal or background levels of these toxins in seals.

Morbillivirus in monk seal mass mortality

Article Abstract:

Researchers have investigated the possible danger of morbillivirus infections to extremely endangered pinnipeds such as the Mediterranean monk seal. This involved looking at 17 samples collected from the hearts of dead monk seals. It was possible to identify a morbillivirus in seven of these samples. This was found to be most closely related to the previously described dolphin morbillivirus. Researchers found no paralytic shellfish poison in seal carcasses or in a composite mussel sample from the region from which the dead seals were collected.

Did algal toxins cause monk seal mortality?

Article Abstract:

Intoxication by algal toxins seems to be the most likely explanation for sudden deaths within a population of Mediterranean monk seals off the coast of the western Sahara. It has been established that the dead seals were in a good nutritional state, but their lungs were congested and their lungs and airways filled with fluid. Evidence was found for poisoning by paralytic toxins, which has been proposed as a possible aetiology in the mortalities of a number of marine mammals.